Tier 2 benthos

Processing of sorted samples  (see Tier 1 for field methods and sorting)

1. Taxonomic Identifications and Enumeration

Once the samples are picked and associated quality control checks done for completeness and accuracy (Tier 1), species identifications must be performed by qualified taxonomists (see section 1.1 below).All organisms found in the samples should be enumerated and identified to the lowest practical taxonomic level (generally species). A list of selected basic taxonomic references for the Pacific Northwest is provided herein. The Washington State Department of Ecology PSEMP technical library contains extensive invertebrate taxonomic reference materials, including texts and primary literature in invertebrate taxonomic studies.  The production of photographic iconographs are being discussed for the SSAMEx program, and have been used to advantage elsewhere (Camburn et al. 1984-1986). Voucher sheets are being generated for most Pacific NW species by the Washington State Department of Ecology (WS DOE) and are an excellent source of information for taxonomic identifications. 

Marine benthos invertebrate samples are generally identified by 2-4 taxonomist experts, specializing in particular taxonomic groups.   This collaborative approach minimizes taxonomic errors. Any disagreements are investigated, and results of findings are incorporated into the existing data set before it is finalized.  Identifications are done primarily with a stereomicroscope (10-100x magnification) and a compound microscope as necessary (100-400x magnification). Depending on the group of interest, additional laboratory techniques are used, including dissection, staining, digestion of tissue, and clearing.

If organism fragments are present, only anterior portions are counted, but all fragments are retained. Fragments are checked by the taxonomists, to look for the presence of anterior portions of organisms and to confirm that fragments had been placed within the correct major taxonomic group. Fragments which are not anterior sections are kept with other faunal specimens but NOT counted (see Tier 1 sorting). Identifications must be checked for consistency by the principal taxonomist.  Identified organisms and fragments of organisms are stored in 70% ethanol in glass storage vials, sealed with paraffin and labelled with the sample number, major group, taxonomist, and date.

1.1 Training

Because of the complexity and diversity of marine benthic organisms, taxonomists must undergo extensive hands-on training at a reputable taxonomic company or monitoring organisation.  This training further requires access to detailed reference collections (section 4 below) as well as voucher sheets (when available) and taxonomic literature for the region.  This limits options for training to academic institutions and recognized, existing marine taxonomic organizations.  

All taxonomists must have a record of >95% agreement from external, qualified taxonomists on their identifications before processing samples independently. 

As possible, all taxonomy staff members are encouraged to attend workshops and/or conferences to obtain the latest information on the advances in taxonomy.  Training exchanges of key taxonomic personnel between accredited laboratories is highly recommended, to help synchronize methodologies and produce consistent results coastally. At present, the SSAMEx program is promoting such a training exchange between an accredited BC consulting company and the WS DOE, to promote harmonization of methods. 

2. Data Handling

The taxonomists must use bench sheets for IDs and counts, as per Environment Canada guidelines (see CABIN manual). The use of bench sheets creates a permanent record of preliminary data and notes, and thus auditable data files. These are invaluable for tracking errors and discrepancies. 

Data are entered into a spreadsheet and completely double-checked against bench sheets for entry errors.  These checked data sheets are kept filed for 10 years, along with original bench sheets. Electronic files are kept in duplicate in perpetuity, with data backups performed regularly.  

The inclusion of a regionally viable taxonomic coding system for species names is critical to ensure taxonomic consistency over studies and time, thus allowing data exchange and harmonization for the region.  In BC, this system has been developed and published in Macdonald et al. (2010) and a masterlist of ~3000 taxa is available to any SSAMEx partner for data entry (contact B. Burd, SSAMEx coordinator, Vancouver Aquarium).   In Washington State, NODC codes are used for the same purpose.  A synchronization of these two coding systems (double-coding) is planned as part of the SSAMEx program in the near future.  As an option, trophic coding is also available (Macdonald et al., 2010) to complement the taxonomic coding in BC. 

Recommended data format for the SSAMEx program includes a long-form datasheet in text or EXCEL format including columns as follows: 

Table x.  Example of recommended long format data entry for SSAMEx Tier 2 data exchange.  This format is the most efficient for pivot tables and summaries for data analyses. Auxilliary tables should include geo-positional data, depths, and any related sediment data.  ANNE = Annelida; POER = Errantiate Polychaete

AgencyProjectYearSample DateSample -ReplicateTaxa typeGroup codeFamily codeSpecies codeTaxon NameStageTotalMean bio (g)Unique taxa countComments
DFOJdFbaseline201512-Apr-151-1ANNEPOER02020710Bipalponephtys cornutaA40.011 
DFOJdFbaseline201512-Apr-151-1ANNEPOER02140300Eteone longa complexInt20.0021 
DFOJdFbaseline201512-Apr-151-1ANNEPOER02280450Exogone loureiA161.11 
DFOJdFbaseline201512-Apr-151-1ANNEPOER01800500Glycera nanaA122.561 
DFOJdFbaseline201512-Apr-151-1ANNEPOER01800500Glycera nanaInt20.15  
DFOJdFbaseline201512-Apr-151-1ANNEPOER01800500Glycera nanamega12.56  
DFOJdFbaseline201512-Apr-151-1ANNEPOER02200593Harmothoinae indet.J10.00011 
DFOJdFbaseline201512-Apr-151-1ANNEPOER01980615Lumbrineris cruzensisA50.0011 
DFOJdFbaseline201512-Apr-151-1ANNEPOER01981040Lumbrineris lutiA210.00011Previously Scoletoma luti
DFOJdFbaseline201512-Apr-151-1ANNEPOER01981040Lumbrineris lutiInt20.0002 Previously Scoletoma luti
DFOJdFbaseline201512-Apr-151-1ANNEPOER01981040Lumbrineris lutiJ10.0001 Previously Scoletoma luti

3. Taxonomic Verifications

Re-identification of 5% of samples for each project is recommended, as required/requested from the client. On a more general basis, 1-2% of all marine benthic samples from a given taxonomic laboratory will be sent for bulk re-identification by a second accredited lab every year to both assess  percent agreement, and inform professional development needs.  Results of these inter-calibrations should be available upon request.

Both the QC and primary taxonomists receive rigorous external training (section 1.1), and must have a record of >95% external agreement on their identifications before processing samples independently. A third Quality Control (QC) Taxonomist double-checks all new identifications which have not yet been externally verified. New and unusual taxa are also sent for external verification.  

4. Reference Collections

Reference collections are useful for confirming identifications, ensuring consistent taxonomy, and in training personnel. For comparative purposes and quality control, the maintenance of reference collections of organisms are strongly recommended. 

For the SSAMEx program it is recommended that three distinct size classes be included in the reference collection for each taxon (see section 5 below).  These include adults, sub-adults (non-reproductive stage) and juveniles (recently settled).  Reference specimens are stored in 70% ethanol in O-ring sealed cryogenic storage vials, with labels indicating specimen identity, taxonomist, sample number, and date. 

A complete reference collection with 5-10 (Green 1994) specimens of each taxon and size class should be compiled and archived for each survey area.  These collections are updated as appropriate (i.e., with any new species or taxon which are newly collected). Each species should be verified by an external taxonomist and should encompass identified organisms from each area in the survey and the location of this collection reported. 

Reference collection samples should be housed in long-term storage vials, with specimens from different samples stored separately. These specimens were likely originally fixed in formalin (5-10%; buffered) and transferred to ethanol (70%) for analysis. Reference vials should contain 70% alcohol. 

5.1 Existing benthic infaunal reference collections

The Washington State Department of Ecology’s (WSDOE) Marine Sediment Monitoring Unit houses a large collection of marine infaunal invertebrate organisms from Puget Sound. The collection contains over 2400 specimens from 908 taxa, and includes all reference and voucher specimens collected from the Puget Sound Environmental Monitoring Program (PSEMP) conducted since 1989, as well as some earlier Puget Sound studies. The WS DOE have developed, and have extensive experience applying, a standardization review process for QA/QC of taxonomic nomenclature in data generated by numerous contracted taxonomists. This review process was developed by Ecology personnel while reviewing 20 years of PSAMP data. It is a method of comparing taxa designations between stations and between years of a study to locate nomenclature and identification discrepancies invariably generated when multiple taxonomists work on a project. The process attempts to minimize the unavoidable inconsistencies in taxonomic nomenclature due to changing taxonomic nomenclature in the published literature and to assignment of species names by taxonomists with varying backgrounds and skill levels.  The standardization review process is applied to all taxonomic data to ensure consistency among different taxonomists both within and between years. The process will be applied at regular intervals as data are generated, so that inconsistencies can be resolved and data can be standardized while the taxonomic identification of samples is still being conducted. 

Taxonomists in Washington State DOE also generate taxonomic voucher sheets describing species given provisional designations to ensure standardized identifications among different taxonomists and across the years. Washington State taxonomic standards reflect those of ITIS (Integrated Taxonomic Information System), WoRMS (World Register of Marine Species), SCAMIT (Southern California Association of Marine Invertebrate Taxonomists) or the most recent primary literature, as recorded in our taxonomic database. All taxa are subject to review once/year to ensure taxonomic information is kept up to date.

In British Columbia, reference collections are typically constructed for each project, and are housed in various locations.  The primary storage of reference collections for BC is at Biologica Environmental Services, Victoria, BC. These are primarily size-categorized reference collections of benthic infauna and sediment epifauna (contact Dr. Tara Macdonald)  constructed for surveys from sampling regions spanning Northern and Southern Strait of Georgia and adjacent Inlets; Victoria and Esquimalt Harbours; The Strait of Juan de Fuca; and various locations along the BC coast including Haida Gwaii and Northern Vancouver Island.  All taxa in these reference collection have been independently verified by external taxonomists, and all new additions are sent for external verification.  Each taxon is checked for taxonomic validity at least once/year, and synonyms and updates are recorded in the BC taxonomic database. The BC taxonomic database includes a taxonomic coding system developed and used to maintain up to date taxonomic nomenclature and changes, and to standardize species identifications over the years (Macdonald et al., 2010).   Nomenclature follows SCAMIT. 

4. Size classification

As part of the identification process, each organism is assigned to one of three size/age categories according to their size and stage of development (adult, intermediate, or juvenile – see section 6 below) based on best professional judgement. These are not necessarily developmental categories, but instead refer to the size of the organism. Juveniles are generally immature specimens in early stages of development, but intermediates and adults may or may not be in a reproductive state at the time the sample was taken. As such, the intermediates may be small adults or ‘subadults’, which have adult features but have either not attained the typical adult body size. Immature and juveniles must be counted and enumerated separately from adults whether or not they can be identified to species. This is done for two purposes;

  1. So that the adult assemblage can be analyzed without the confounding influence from transient juveniles. This is because newly settled benthic forms have different survival characteristics than adults, which have been present in the sediments much longer and integrate the effects of habitat perturbations over time. Dramatic variations in immature settlement between nearby samples within physically homogeneous habitats may be indicative of varying levels of stressors, and;
  2. The three stages can be separately analysed for mean species-specific and size specific wet weight biomass (see section 6 below).  This level of detail ensures that consistent and accurate assessments of infaunal organic biomass and production can be made and compared between sites and based on habitat variables (Burd, 2014). 

Standard sizes are constantly updated and reviewed with additional information. As a general rule, adult specimens are the largest in the sample; intermediates are smaller (by >5-10x) but still identifiable to the same level as the adults as they share all adult features; and juveniles are too small and underdeveloped to assign to genus and/or species, unless these are distinctive taxa.  Juveniles not classified to species can be interpolated to belong to a specific taxon if there are adults or intermediates of only 1 species matching the juveniles. Otherwise, they must be categorized as a separate taxon for inclusion in reference collections.  An example of size categories used for molluscs is given in Appendix A.

6. Wet Weight Biomass Determinations

Because precise biomass measurements are time consuming and problematic (c.f. Crisp 1984) it is only feasible to take blotted wet-weight measurements of representative sized adults, intermediates and juveniles of each taxon.  Since the method is non-destructive, the reference collection may be used for this purpose prior to external verification or archiving. Mean species/size specific wet weights should be recorded along with mean width, lengths. Polychaete reference specimens are typically weighed without tubes. However, where there are large abundances of small tube-worms this may not be feasible.  In this case, wet weights given for a taxon should specify whether there are tubes included or not. 

Wet weights (WW) are performed with a balance that is accurate to 0.1-0.01mg. The accuracy of 5 decimal places (0.01 mg) is required for small taxa but is not necessary. If few taxa are beyond detection limits, these are reported as 0.00005 mg. Prior to weighing, organisms are removed from ethanol, blotted on a Kimwipe or filter paper, and the first weight upon placement in the balance recorded. One cannot wait for stabilization of the balance reading as ethanol evaporates quickly, and small organisms will dry out.  

Individual organisms weighing more than 2 grams are classified as megafauna.  Per-taxon biomass requires extraordinary handling of organisms that are megafauna  (individual specimens >2g (see below). Larger organisms are blotted for 30 seconds, placed on the balance pan, and then air-dried for 1.5 minutes (to allow some of the alcohol to evaporate) before the weight was recorded. The 1.5-minute waiting period was selected in 2001 after comparing the results of repeatedly weighing organisms using various methods. It was determined that a 1.5minute waiting period before weighing was unnecessary for smaller organisms. 

Biomass estimates are a critical component of reference collections. Specific procedures to streamline biomass measurements resulting in the most accurate and cost-effective data have been developed over the past 15 years and can be summarized as follows:  

1.  During sorting, remove and separately weigh all large fauna suspected to be 2 g or heavier. These will be categorized as megafauna.  If there is more than 1 specimen of a given taxon in a sample, these can be counted, weighed in bulk and an average mega weight recorded for that taxon and sample. 

2. For the remaining specimens; during the production of a reference collection, include at least 10 specimens from three size classes for each identified taxon.  This may not be possible for rare taxa. Measure mean wet weights for each size class (adult, intermediate and juvenile) record for that taxon, size group and sample.  This will typically be done in full (for all taxa and size groups) the first time a survey is done in a region, if there are no previous reference collections available.  Thus the reference collection includes not only verified specimens identified to the lowest possible taxonomic unit, but three size classes for each taxon with average weights for each size class.

3. In a case where there are megafauna and regular sized fauna of the same taxon for a given sample, it is critical that the mean adult wet weight (non-megafauna) should be calculated WITHOUT including the megafauna, to avoid over-biasing of wet weight results for a given sample.  In most cases, this mean adult weight will already be available from the reference collection measurements of regular (non-mega) fauna.  It is imperative that all megafauna in all surveys be weighed in full, since these taxa can seriously bias biomass assessments.

4.  For repeat surveys in a given region with an existing detailed reference collection (as in item 2 above), it may not be necessary to do biomass measurements for all taxa and size groups.  In this case, only new taxa will have to be weighed as described in 2 above, with one exception.  Any dominant fauna likely to affect biomass estimates that appears upon comparison with reference collections to have changed in general size or shape should be re-weighed and added to the reference collection as a time-specific item.  This can occur for some opportunistic taxa, where size distributions of the population depend on sediment enrichment.  This is least likely to occur in background samples unaffected by anthropogenic inputs.

5.  New, complete reference collections with biomass measurements should be developed for coastal regions without prior reference material, as part of initial monitoring survey programs.  It may not be suitable to extrapolate weights for distant regions with very different hydrographic and sedimentation characteristics. 

7. Biomass Data Sharing 

A general taxonomic/size class biomass database will be maintained as part of the SSAMEx program.  A historical biomass database will be published in a publicly available government technical report for the purpose of filling in missing weights for rare taxa, or to compare size distributions of taxa of interest from different regions.  When used, the historical biomass database source must be properly referenced.  As part of the data-sharing component of SSAMEx, geo-spatial biomass data from reference collections contributed by participating members will be archived and made available to all SSAMEx partners. 

8. Optional Shell Staining / Rust Classification of Axinopsida serricata

The use of iron oxide shell staining on the shells of abundant, shallow burrowing bivalves has been useful for determining time-integrated (over the lifetime of the bivalves) near-surface sediment redox conditions, particularly related to organic enrichment (Burd et al., 2008). In BC, the small bivalveAxinopsida serricata has been found to be sufficiently abundant, consistent and ubiquitous in mid-depth coastal areas to be a useful tool for tabulating proportional population shell staining patterns.  However, the use of other taxa for this purpose should be possible.  For the SSAMEx program, this tool may be of limited use since data is primarily from background areas unlikely to be affected by organic enrichment.  However, a detailed comparison of background shell staining patterns with those for relevant management areas can be very useful.  It is considered an optional or value-added component of Tier 2 monitoring.

During taxonomic processing, the bivalve shells are each classified based on the degree of rust deposition on the shell. Sorting of specimens and grading of the rust deposition are performed by the mollusc taxonomist. Rust classification (0 = no rust to 3 = heavy rust) are performed concurrently with identification of the bivalves in a given sample. Individual samples are handled in the following manner.

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The A. serricata are divided into classes by size. The categories (adult, intermediate, and juvenile) were determined by measuring the shell length. This was determined by passing each specimen over a piece of graph paper with 1 mm gradations that could be viewed through the petri plate. Adults are defined as being larger than 2.70 mm, intermediates measured between 2.70 mm and 0.86 mm, and juveniles less than 0.86 mm. Each age class is placed in a separate section of the dish. The taxonomist divides each specimen into four rust categories coded as follows and illustrated in Burd et al. (2008):

  • 0 – No rust
  • 1 – Rust in a small area
  • 2 – A thin layer of rust in a medium area or a thick layer of rust in a small area
  • 3 – A thin layer of rust in a large area or a thick layer of rust over a medium or large area

The specimens are moved into different parts of the dish in the process of rust categorization. Each grouping is counted using a hand counter and recorded on a bench sheet. In samples containing more A. serricata than could be conveniently handled in one dish, a portion can be transferred to another dish and processed independently. The counts are added together on the bench sheet when rust categorization is complete.

Upon completion of this assessment the A. serricata are stored in separate vials by project and sample number.

Although A. serricata is clearly a dominant subtidal bivalve in the Salish Sea, other dominant, shallow burrowing bivalves may dominate in a particular study. The monitoring agency is encouraged to assess shell staining of other, abundant bivalves in a similar manner. 

9. Summary of QA/QC procedures for Tier 2 benthos;

1. Re-identification of 5% of samples for each survey should be done by a different, qualified QC taxonomist (trained as described in section 1.1), who also double-checks any new species which have not been externally verified.  Any taxonomic changes or discrepancies should be reported, with the resulting survey report corrected. New and unusual taxa should always be sent for external verification. 

2. One to two percent of all marine benthic samples from a given taxonomic laboratory may be sent for bulk re-identification by a second accredited lab every year to both assess  percent agreement, and inform professional development needs.  Results of these inter-calibrations should be available upon request through the SSAMEx program.

3. The taxonomic report must include a complete listing and contact details for external taxonomic authorities used for initial identifications as well as verifications, location of reference collection and tracking data for taxonomic verifications.

4. Bench sheets (hand-notes of taxonomists) must be retained for ten years at a minimum to check for anomalies or transcription errors.

5.  During the identification process, both bulk identified specimens and voucher/reference specimens are placed in tightly-sealed vials with appropriate internal labelling, and organized into labelled boxes (specimens) or Cornell trays (voucher/reference specimens). One to two mL of glycerin is added to each vial to prevent complete desiccation, and topped up with clean 70-80% ethanol. Each vial is sealed with parafilm around the cap.  

6. The sorted, preserved and identified samples from each survey should be retained in an appropriate storage facility for at least 5 years, or until it is determined that no further information will be required from the samples.

8. Example Taxonomic and other References

Abbott, R.T.  1974.  American seashells.  (2nd Ed.) Van Nostrand Reinhold Co., New York.  633 pp.

Appy, T.D., I.F. Linkletter, and M.J. Dadswell.  1980.  A guide to the marine flora and fauna of the Bay of Fundy: Annelida: Polychaeta.  Fishereies and Marine Service, Technical Report No. 920.  124 pp.

Austin, W.C., 1985. An Annotated Checklist of Marine Invertebrates in the Cold TemperateNortheast Pacific,Vol. 1, 2 and 3, Khoyatan Marine Laboratory, Cowichan Bay, B.C., Contract to Fisheries and Oceans.

Baker, H.R. 1980. Key to the Common Tubificid Species of the Northeast Pacific, Manuscript from Oligochaeta Workshop.

Banse, K.  1972.  Redescription of some species of Chone Kroyer and Euchone Malmgren, and three new species (Polychaeta: Sabellidae)  Fishery Bulletin 70(2):459-495.

Banse, K and K.D. Hobson, 1974. Benthic Errantiate Polychaetes of British Columbia and Washington, Bulletin of Fisheries Research Board of Canada, Bulletin 185,  Ottawa.

Bednarik, A.F., and W.P. McCafferty.  1979.  Biosystematic revision of the genus Stenonema. Can. Fish. Aquat. Sci. Bull. No. 201, 73 p.

Berkeley, C. and E. Berkeley. 1952a. Canadian Pacific Fauna, 9. Annelida 9b (1) Polychaeta  Errantia, University of Toronto Press, Fish. Res. Bd., Canada.

Berkeley, C. and E. Berkeley. 1952b. Canadian Pacific Fauna 9. Annelida 9b (2) PolychaetaSedentaria, University of Toronto Press, Fish. Res. Bd., Canada.

Blake, J.A.  1971.  Revision of the genus Polydora from the east coast of North America (Polychaeta: Spionidae).  Smithson. Contr. Zool. 75:1-32.

Blake, J.A.  1991.  Revision of some genera and species of Cirratulidae (Polychaeta) from the western North Atlantic.  Ophelia Suppl. 5:17-30.

Bousfield, E.L.  1960.  Canadian Atlantic seashells.  Canada Department of Northern Affairs and Natural Resources, National Museum of Canada.  72 pp.

Bousfield, E.L. and E.A. Hendryks, 1994. The Amphiphod Superfamily Leucothoidea on the Pacific Coast of North America.  Family Pleustidae: Subfamily Pleustinae, Systematics and Biogeography, Amphipacific Vol.1, No. 2.

Bousfield, E.L. and E.A. Hendryks. 1995a. The Amphipod Family Pleustidae on the Pacific Coast of North America.  Part III, Subfamilies Parapleustinae, Dactylopleustinae,and Pleusirinae: Systematics and Distributional Ecology, Amphipacifica Vol.II, No.1.

Bousfield, E.L. and E.A. Hendryks.1995b. The Amphipod Superfamily Eusiroidea in the North Pacific Region.I Eusiridae: systematics and distributional ecology, Amphipacifica Volume 1, Number 4.

Bousfield, E.L. and P.M. Hoover. 1995. The Amphipod Superfamily Pontoporeioidea on the Pacific Coast of North America. II. Family Haustoriidae.  Genus Eohaustorias J.L. Barnard: Systematics and Distributional Ecology, Amphipacifica, Vol. II, No. 1.

Bousfield, E.L., and J. A. Kendall. 1994. The Amphipod Superfamily Dexaminoidea of the North American Pacific Coast; Families Atylidae and Dexaminidae: Systematics and Distributional Ecology, Amphipacifica Vol. 1, No. 3.

Brinkhurst, R. O.  1982.  British and other marine and estuarine oligochaetes.  Synopses of the British Fauna, N.S. 21: 1-127.

Burd, B., Macdonald, R.W., van Roodselaar, A. and Wright, C.A., 2008. Axinopsida serricata shell encrustation as a geochemical indicator of organic enrichment conditions in sediments in the southern Strait of Georgia, British Columbia, Canada. Marine Environmental Research, 66(S101-S111).

Burd, B. 2014  Distribution, inventory and turnover of benthic organic biomass in the Strait of Georgia, Canada, in relation to natural and anthropogenic inputs.  Mar. Poll. Bull. (on line) http://dx.doi.org/10.1016/j.marpolbul.2014.03.004

Butler, T.H..1983. Shrimps of the Pacific Coast of Canada, Bulletin 202, Dept. of Fish. And Oceans, Ottawa.

Camburn, K.E., J.C. Kingston and D.F. Charles (eds.).  1984-1986.  PIRLA Diatom Iconograph.  Contains 53 photographic plates and 1059 figures, plus figure legends.  PIRLA unpublished Report Series, Report No. 3.  Indiana University, Bloomington, Indiana.

Clarke, A. H. 1981. The freshwater molluscs of Canada. National Museum of Natural Sciences. Ottawa, Ontario. 446p.

Coates, K. A.,1980. Keys to Intertidal Genera and species of Enchytraeidae found in British Columbia, Manuscript from Oligochaeta Workshop, U. Vic.

Crisp, D.J. 1984.  Energy flow measurements, pp. 284-370 in Holme, N.A., McIntyre, A.D. (eds). Methods for the study of marine benthos.  IBP Handbook 16.  Blackwell Scientific Publications.  387 pp.

Cutler, E.B.  1973.  Sipuncula of the Western North Atlantic.  Bull. Am. Mus. Nat. Hist. 152(3):1-204.

Fournier, J.A., and M.E. Petersen.  1991.  Cossura longocirrata –  Redescription and distribution, with notes on reproductive biology and a comparison of described species of Cossura (Polychaeta: Cossuridae).  Ophelia Suppl. 5:63-80.

Gosner, K.I.  1971.  Guide to the identification of marine and estuarine invertebrates.  J. Wiley and Sons.  New York.  693 pp.

Green, G. 1994. Protocols for reference and voucher collections of aquatic invertebrates stored at the Royal British Columbia Museum. DOE-FRAP 1994-15.

Hart, J.F.L.1982. Crabs and Their Relatives of British Columbia, Handbook No. 40, B.C. Provincial Museum.

Hay, D.E., Waters, R.D. and Boxwell (eds.) 1996.  Proceedings Marine Ecosystem Monitoring Network Workshop, Nanaimo, B.C. March 28-30. 1995.  Can. Tech. Rep. Fish. Aquat. Sci. 2108. 160pp. 

Hobson, K.D. and K. Banse. 1981. Sedentariate and Archiannelid Polychaetes of British Columbia and Washington, Bulletin 209, Ottawa.

Keen, A.M. and E. Coan. 1974. Marine molluscan genera of western North America. Stanford University Press.

Kozloff, E.N. 1987. Marine Invertebrates of the Pacific Northwest, Univ. of Wash. Press.

Lambert, P. 1981. The sea stars of British Columbia, B.C. Provincial Museum Handbook No. 39.

Laubitz, D.R.  1972.  The Caprellidae (Crustacea, Amphipoda) of Atlantic and Arctic Canada.  National Museum of Canada, Publications in Biological Oceanography, No. 4.  82 pp.

Macdonald, T.A., Burd, B., Macdonald, V.I. and van Roodselaar, A., 2010. Taxonomic and feeding guild classification for the marine benthic macroinvertebrates of the Strait of Georgia, British Columbia., Can. Tech. Rep. Fish. Aquat. Sci. 2874, 63pp.

Santa Barbara Museum of Natural History (SBMNH). 1994a. Taxonomic Atlas, Vol. 1, Platyhelminthes, and Nemertea, Santa Barbara, California, 1994

Santa Barbara Museum of Natural History (SBMNH). 1994b. Taxonomic Atlas, Vol. 2, Porifera.

Santa Barbara Museum of Natural History (SBMNH). 1994c. Taxonomic Atlas, Vol. 4, Oligochaeta and Polychaeta: Phyllodocidae to Paralacydoniidae.

Santa Barbara Museum of Natural History (SBMNH) 1995a. Taxonomic Atlas, Vol.5, The Annelida, Part 2 Polychaeta: Phyllodocida (Syllidae and Scale-Bearing Families), Amphinomida and Eunicida.

Santa Barbara Museum of Natural History (SBMNH). 1995b. Taxonomic Atlas, Vol. 12, The Crustacea, Part 3, The Amphipoda.

Santa Barbara Museum of Natural History (SBMNH). 1995c. Taxonomic Atlas, Vol. 13, The Bryozoa,

Santa Barbara Museum of Natural History (SBMNH). 1996a. Taxonomic Atlas, Vol. 6, The Annelida, Part 3  Polychaeta: Orbiniidae to Cossuridae.

Santa Barbara Museum of Natural History (SBMNH). 1996b. Taxonomic Atlas, Vol. 9, The Mollusca, Part 2  The Gastropoda.

Santa Barbara Museum of Natural History (SBMNH). 1996c. Taxonomic Atlas, Vol. 14, Miscellaneous Taxa.

Santa Barbara Museum of Natural History (SBMNH). 1997a. Taxonomic Atlas, Vol 10, The Pycnogonida, The Crustacea Part 1  The Decapoda and Mysidacea, 1997

Santa Barbara Museum of Natural History (SBMNH). 1997b. Taxonomic Atlas, Vol. 11, The Crustacea Part 2, The Isopoda, Cumacea and Tanaidacea.

Schultz, G.A., 1969. The Marine Isopod Crustaceans, Wm. C. Brown Co., Dubuque, Ia.

Steele, D.H., and P. Brunel.  1968.  Amphipoda of the Atlantic and Arctic coasts of North America: Anonyx (Lysianassidae). J. Fish. Res. Bd. Can.. 25(5).

Thorson, G. 1957. Bottom communities(sublitorral or shallow shelf). In Treatise on Marine Ecology and Paleoecology.J.W. Hedgpeth, ed.Vol 1, pp. 461-534.Memoirs of the Geological Society of America 67.

Wallace, N.A.  1919.  The Isopoda of the Bay of Fundy.  Univ. of Toronto Studies, Biol. Series No. 18.  42 pp.

Appendix A.  Size classifications for Molluscs. Note that specimens suspected of having biomass > 2 g wet weight are classified as “mega” and weighed individually

Species NameAdultIntermediateJuvenile
 > mm < mega > mm < adult > mm < intermediate
BIVALVIA   
Acila castrensis206.62.2
Adontorhina cyclia310.3
Astarte elliptica3511.63.8
Axinopsida serricata82.60.9
Bankia setacea206.62.2
Cardiomya pectinata4013.34.4
Chlamys hastata8026.68.9
Chlamys rubida7123.77.9
Clinocardium blandum5016.65.5
Clinocardium ciliatum7023.37.8
Clinocardium nuttalli14046.615.5
Compsomyax subdiaphana8528.39.4
Crenella faba1551.7
Cryptomya californica3712.34.1
Cyclocardia ovata268.62.8
Cyclocardia ventricosa2793
Delectopecten vancouverensis45155
Ennucula tenuis175.71.9
Hiatella arctica78268.6
Kellia suborbicularis31103.4
Kurtiella compressa103.31.1
Kurtiella tumida51.60.5
Lucinoma annulatum8227.39.1
Lyonsia californica42144.7
Macoma balthica45155
Macoma brota65227.2
Macoma calcarea60206.3
Macoma carlottensis30103
Macoma elimata3511.63.8
Macoma golikovi5016.65.5
Macoma iniquinata5518.36.1
Macoma nasuta75258.3
Macoma yoldiformis258.52.7
Megayoldia martyria30103.3
Megayoldia thraciaeformis6521.67.2
Mendicula ferruginosa3.21.10.4
Modiolus modiolus1806020
Musculus glacialis4013.34.4
Mya arenaria1505016.6
Mya pseudoarenaria11036.712.2
Mytilus trossulus903010
Neaeromya rugifera227.32.4
Nemocardium centifilosum258.32.7
Nuculana cellulita165.31.8
Nuculana hamata1241.3
Nuculana minuta1862
Nuculana penderi1551.7
Nuculana pernula258.52.7
Nutricola tantilla931
Nuttallia obscurata57196.3
Pandora bilirata1551.6
Pandora filosa258.52.7
Pandora wardiana5518.36.1
Panopea abrupta20066.622.2
Parvilucina tenuisculpta134.31.4
Pododesmus macrochisma12842.714.2
Protothaca staminea8026.68.9
Saxidomus giganteus1364515
Scintillona bellerophon51.60.5
Solamen columbianum113.71.2
Solemya pervernicosa60206.7
Solen sicarius10334.311.4
Tellina carpenteri258.52.7
Tellina modesta206.72.2
Thracia trapezoides6521.77.2
Thyasira flexuosa1241.3
Turbonilla sp. 1241.3
Venerupis philippinarum7023.37.7
Xylophaga washingtona620.6
Yoldia hyperborea5016.65.5
Yoldia myalis30103.3
Yoldia seminuda4013.34.4
    
GASTROPODA   
Acteocina cerealis144.71.6
Acteocina culcitella175.61.8
Admete sp.12.74.231.4
Alia tuberosa103.31.1
Alvania compacta/rosana2.60.90.3
Amphissa columbiana30103
Amphissa versicolor196.32.1
Astyris gausapata134.31.4
Balcis micans134.31.4
Batillaria attramentaria (cumingi)5016.75.6
Bittium munitum/Lirobittium attenuatum103.31.1
Boreotrophon orpheus258.32.7
Caecum crebricinctum620.6
Calyptraeidae indet. (Calyptraea fastigiata)258.32.7
Cecina manchurica82.60.9
Crepipatella dorsata258.32.7
Cryptobranchia concentrica237.72.6
Cryptonatica affinis258.32.7
Cylichna attonsa1241.3
Dendronotus subramosus33113.7
Euspira palida4013.34.4
Diaphana californica51.60.5
Haminoea vesicula 2062
Haminoea virescens2062
Lacuna variegata165.31.7
Lacuna vincta165.31.7
Lirularia lirulata/succincta82.60.8
Littorina scutulata196.32.1
Littorina sitkana258.32.7
Loy thompsoni (Corambe sp. 1)6.52.20.7
Lottia alveus parallela (Lottia parallela)1241.3
Margarites rhodia103.31.1
Margarites pupillus 175.61.8
Melanochlamys diomedea1551.6
Nassarius fraterculus1551.6
Nassarius mendicus227.32.4
Odostomia angularis620.6
Odostomia sp.103.31.1
Ophiodermella cancellata134.31.4
Propebela/ Oenopota (Mangeliidae indet.)258.32.7
Puncturella cucullata4013.34.4
Puncturella galeatea2062
Solariella sp.20 (16)6 (5.3)2 (1.8)
Tectura fenestrata268.62.8
Trichotropsis cancellata4013.34.4
Turbonilla sp. 1241.3
Vitreolina clumbiana103.31.1
   
APLACOPHORA   
Chaetoderma argenteum4013.34.4
Falcidens longus289.33.1
Limifossor fratula7.42.50.8
   
POLYPLACOPHORA   
Lepidozona interstincta30103.3
Leptochiton rugatus165.31.8
Mopalia phorminx2062
    
SCAPHOPODA   
Antalis pretiosum5016.75.6
Cadulus aberrans(13) 103.31.1
Gadila tolmiei (Cadulus tolmiei)1551.6
Pulsellum salishorum72.30.7
Rhabdus rectius (100) 30103.3